MIAMI (CBS4) – A problem has arisen for a 21-year-old University of Miami student who turned herself in Tuesday to begin a prison sentence for a deadly drunk driving accident.

Ivanna Villanueva, her family and attorney arrived at the Miami-Dade courthouse Tuesday morning for a final hearing before she would officially surrender. As part of the process, she was required to take a drug test. Villanueva was unable to complete the first test.

During a second test, the result tested positive for a banned substance, sources told CBS4.

Miami-Dade State Attorney’s Office spokesman Ed Griffith would not confirm this, but did acknowledge there was an issue with the test.

“The issues are relating to concerns related to medical prescriptions which may or may not be posing a problem,” was all Griffith would say on the matter.

Griffith told CBS4’s Peter D’Oench, “What I can say is that there will be an analysis tomorrow in court explaining whether or not we have doctor’s orders that are being followed and can raise a concern or not.”

The hearing was re-set for Wednesday where a full analysis of the test result will be presented in court. Villanueva’s family will also have to produce a note from her doctor which states that he prescribed her the medication.

The terms of Villanueva’s plea deal include three years in prison, 15 years of probation and thousand hours of community service for the deadly 2011 accident which claimed the life of Eyder Ayala. Villanueva will also have to make a donation to Mothers Against Drunk Driving on the anniversary of Ayala’s death.

If Villanueva fails to pass the drug test, her sentence will radically change.

“Illegal substance abuse as part of the deal can lead to a 15-year prison term. That’s why it’s extremely important. You have to be extremely cautious and extremely correct. If it’s the wrong thing, it would be an injustice on top of another injustice,” said Griffith.

The accident occurred at the intersection of LeJeune Road and Majorca Avenue. According to police, Villanueva was driving at a high rate of speed when she slammed into the rear Ayala’s car. Ayala, a mother to five and grandmother to seven, died at the scene.

Ayala was going home from work. She was an Assistant Manager at a McDonald’s restaurant at SW 42nd Ave. and SW 9th St. and had worked there for 20 years.

Ayala’s family has filed a multi-million dollar lawsuit against Villanueva and her father, saying he is liable for her conduct. The multi-million dollar lawsuit claims Villanueva was, “speeding, negligent and reckless” on the night of the accident. It also states that Villanueva showed “extreme recklessness and a wanton disregard for life.”

The impact from the crash was so severe that Ayala’s trunk was pushed into the front seat. She was killed instantly.

“I would like to say that she killed the most precious person. I think she was the most valuable person in our family. We don’t have her anymore. We are not going to see her anymore. I feel nobody should be drinking and driving, especially underage people,” Ayala’s only daughter, Brenda Vazquez, told D’Oench on Oct. 5th of 2011.

“My mom was the most loving, exceptional, wonderful person,” Vazquez said. “There’s just an emptiness. This is a nightmare that I’d like to wake up from. We are distraught. We never thought this would happen.”

In court, shortly after the accident, a Prosecutor said Villanueva had used fake identification papers to get into the Miami Beach nightclub Liv.

Days after the accident, a spokesman for the Villanueva family, Ivan Morales, said “The Villanueva family is exceedingly saddened by the events of this past Sunday. And Ivanna Villanueva is grief stricken over this tragic accident. Everyone in the family wishes to convey their deepest sympathies to the Ayala family at this very, very sad time. Our thoughts and prayers are with them.”